[Extrarespiratory manifestations of Mycoplasma pneumoniae: a case report]

Extrapulmonary manifestations of Mycoplasma pneumoniae are sometimes severe and may even be life-threatening. A 10-year-old patient was hospitalized due to a flu-like illness lasting 48 h with impaired general condition, after an extended stay in Africa. There was an inflammatory syndrome associated with hyponatremia, but malaria was negative. A triple antibiotic therapy with ceftriaxone, amikacin, and josamycin was started. The progression was marked by the appearance of hypoxemia pneumoniae associated with extrarespiratory manifestations. He initially presented with acute polyradiculoneuropathy, followed by thrombotic events associated with polyserositis, polyarthritis, a maculopapular rash, and then a hemophagocytic syndrome. Bacteriological samples isolated M. pneumoniae in nasopharyngeal secretions with a positive serology. The appropriate antibiotic therapy associated with corticosteroids and immunoglobulins led to clinical improvement and the patient progressed toward complete recovery. The pathogenesis of M. pneumoniae infection remains largely unknown. However, two main categories have been proposed. The lung injury is caused by the invasion of the respiratory epithelium, whereas the extrarespiratory manifestations are probably due to immunological disorders. The knowledge of extrarespiratory manifestations and their pathomechanisms allows further adjustments to therapeutic management.